Patent Application
20120261175
1. Technical Field
The present disclosure relates to a printed circuit board (PCB).
2. Description of Related Art
Referring to
What is needed, therefore, is a circuit board which can overcome the limitations described above.
Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
The disclosure, including the accompanying drawings, is illustrated by way of example and not by way of limitation. It should be noted that references to one embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.
Referring to
The printed circuit board 2 further includes a connecting terminal 23. The connecting terminal 23 is placed on one side 29 of the first circuit area 21, for electrically connecting a load (not shown). The printed circuit board 2 can deliver the driving current into the load via the connecting terminal 23, so the connecting terminal 23 can be considered as a load port. The connecting terminal 23 can be a golden finger meeting Universal Serial Bus (USB), Peripheral Component Interconnect (PCI) or other standards. The connecting terminal 23 has an imaginary center line OO′ perpendicular to the side 29 of the printed circuit board 2.
In present embodiment, the operation current of the first circuit area 21 with the connecting terminal 23 formed thereon is greater than that of the second circuit area 22. The first circuit area 21 is electrically connected to the second circuit area 22 via the connectors 24, 25, 26, 27, 28. That is, the current in the second circuit area 22 flows into the first circuit area 21 by passing through the connectors 24, 25, 26, 27, 28, and further gathers to the connecting terminal 23.
The connectors 24, 25, 26, 27, 28 may be resistances, metal-oxide-semiconductor field-effect transistors (MOSFETs) or other impedance components. Based on the distribution of the connection area between the first circuit area 21 and the second circuit area 22, the connectors 24, 25, 26, 27, 28 are to be arranged in such manner, the less a horizontal distance x between the center line OO′ of connecting terminal 23 and one of the connectors 24, 25, 26, 27, 28 is, the larger a vertical distance y between the side 29 of the printed circuit board 2 and that the one connector 24, 25, 26, 27, 28 should be. It can be understood that, the more the connectors 24, 25, 26, 27, 28 close to the center line OO′ of connecting terminal 23, the more the vertical distance y between that connector and the side 29 of the printed circuit board 2, the larger an equivalent resistance between that connector and connecting terminal 23. In present embodiment, the connectors 24, 25, 26, 27, 28 are arranged in steps, which mean that distances between the connectors 24, 25, 26, 27, 28 and center of the connecting terminal 23 (not shown) are almost the same.
Because the current flows into the first circuit area 21 by passing through the connectors 24, 25, 26, 27, 28 would gather to the connecting terminal 23 in a sector whose center coincides with the connecting terminal 23, and the closest connector to the center line OO′ of connecting terminal 23 has larger equivalent resistance, that means the path in the first circuit area 21 with high current density in relation to the connecting terminal 23 has larger equivalent resistance. Therefore, the current in the path of the first circuit area 21 which has higher current density and closer to the center line OO′ of connecting terminal 23 can be conducted into the connectors which are farther from the center line OO′ of connecting terminal 23, such that the current passes through each of the connectors 24, 25, 26, 27, 28 is almost the same, and the current flows into the connecting terminal 23 is uniform, or effectively so, such that high temperature created at one of the connectors 24, 25, 26, 27, 28 can be avoided, the reliability and lifespan of the printed circuit board 2 can be improved.
A current at each connector 24, 25, 26, 27, 28 is obtained based on an exemplary experiment are illustrated as follows in table 1:
As a result, the current passes through each of the connectors 24, 25, 26, 27, 28 is almost the same, thus avoiding a greater current at one of the connectors 24, 25, 26, 27, 28.
Referring to
Referring to
The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the above everything. The embodiments were chosen and described in order to explain the principles of the disclosure and their practical application so as to enable others of ordinary skill in the art to utilize the disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those of ordinary skills in the art to which the present disclosure pertains without departing from its spirit and scope. Accordingly, the scope of the present disclosure is defined by the appended claims rather than the foregoing description and the exemplary embodiments described therein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 100113080 | Apr 2011 | TW | national |
